Technical Abstract:
The effects on behavior during gestation and around farrowing of housing gilts for one parity in individual stalls (n=14; 2.21 m x 0.61 m) or groups of four with individual feeding stalls (n=8; 3.9 m x 2.4 m) were evaluated. The two housing treatments were contained in a single room. Pregnant gilts were limit-fed once per day. Floors were fully slatted with no bedding. Observations of oral/nasal/facial behaviors were made for 2 h after daily feed had been eaten, during wk 7-15 of pregnancy. During wk 4, 8 and 13, the use of stalls at feeding by grouped gilts was was observed. Fights between group occupants were counted during a 24 h period at wk 2, 4, 6, 9 and 13. Gilts were transferred to farrowing crates 5 d before their expected date of parturition, and posture changes recorded for 24 h before the birth of the first piglet; during farrowing; and for 24 h after the birth of the last piglet. The duration of farrowing and inter-birth intervals were recorded. During wk 7 (p<0.01), 8 (p<0.05) and 9 (p<0.05), gestation stall-housed gilts spent more time than group-housed gilts in the 2 h after eating performing oral/nasal/facial behaviors. Group occupants showed little consistency in choice of feeding stall, or stall entry order at feeding. Two fights were observed during wk 2 (1 wk after mixing), and one during wk 6. There were no differences in duration of farrowing, inter-birth intervals, or peri-parturient posture-changing behavior between gilts that had been housed in stalls or groups for gestation. In summary, while grouped gilts displayed less oral behaviors than those housed in gestation stalls there were few other differences. Little fighting occurred among group members after the immediate post-mixing period. Housing gilts in groups of four does not appear to reduce their welfare.